Pseudoteaching with Demos

Pseudoteaching was a concept I have understood and been wary of for a long time.  However, only recently was I able to put a name to the phenomena thanks to a conversation I had with Frank Noschese.  This post is one of several being written about the notion of pseudoteaching today.  Please check out the other posts by visiting the pseudoteaching link page.

Before getting started, I should probably explain what I mean by a demo.  Obviously, “demo” is short for demonstration.  In science (and other content areas), there are a lot of phenomena we want students to witness.  Sometimes having students conduct the procedure to generate the observations is too dangerous, or maybe the procedure must be carried out “just so” or perhaps materials are too expensive to have groups of students carry out the procedures.  In any of these cases, having the teacher demonstrate the procedures to generate the observations is a nice way to still provide students with a concrete experiences.  For a bunch of example science demos, check out sciencefix.com.

So, how is teaching with demos pseudoteaching?  Well, let’s be clear.  There are effective uses of demos in teaching – especially science teaching, but oftentimes demos are not used to promote student thinking.  This post tries to both highlight how the use of demos often leads to pseudoteaching as well as how demos might be more effectively used in instruction.

Demos as Pseudoteaching

Demos are highly entertaining to witness.  I have been to many science education conferences and the “101 demos for your chemistry class” sessions are always packed.  The key attraction of demos is also perhaps their greatest weakness – they’re entertaining.  Students are captivated by demos, but they are captivated by the “whiz-bang” factor, not by a deep understanding of nature that might be used to explain the captivating event.  Too often the point of a demo is to entertain, not to teach.  Sometimes demos are clearly used for instruction, but the demo is simply explained – reflecting lecture-based instruction.

Go back and watch a few of the demos from sciencefix.com.  Notice how the phenomenon is explained to the viewer.  There is no attempt to actively engage the audience in attempting to formulate their own explanations.  There are no questions being asked.  While some might say, “this is a video, not a classroom”, I know that many demos are carried out in much the same way in science classrooms.  While the demonstration might pique students’ interest, too often this interest is used to simply explain to students what happened and why rather than having students attempt to create explanations.

Perhaps more problematic than the “simply explain” approach to demos is the previously mentioned use of demos for entertainment.  While we want kids to be interested in science, crossing education with simple entertainment is problematic.  By trying to make things entertaining (not the same as engaging), we risk sending kids the message that only things that are fun are worth doing.  Instead of using demos as a “whiz-bang” entertainment device, they should be used to engage students’ in deep thought about what they are observing.  The engagement factor of demos IS powerful, but too often, the “hey this is neat” is where the demo ends.  Some teachers even put on demo shows for the school.  This is great, but leaves me asking, why are you not bringing these things into the classroom, and why are you not leveraging student interest to generate deep levels of thinking and having students generate explanation and new questions?

Effective use of demos

Importantly, I am not advocating that teachers not use demos in their classroom.  Like with all things, there are appropriate uses.  As previously mentioned, sometimes pragmatic concerns such as safety or material availability prohibit letting students manipulate the demo directly.  Yet, the demo must be carefully used to generate student thinking and guide student thinking rather than simply explain or entertain students.

Start by asking questions to get students to make observation and make predictions.  When I taught chemistry, I spent a significant amount of time on polar and non-polar interactions.  During this unit I used a demo of mixing oil and water.  I held up two test tubes full of liquid (one is oil, the other is water).  I asked students, “What can you tell me about these liquids?”  The students gave me lots of ideas.  Then, I asked, “What do you think will happen when I add a drop of blue food coloring to the yellow liquid (oil)?” Students eagerly answered this question and were on the edge of their seats with anticipation as I added the drop and it sank to the bottom of the oil.

Once students observe this,  I asked them to talk with their partners to explain why the drop did not mix with the yellow substance.  After a few minutes I had them share some ideas.  Then, based on their ideas I asked them what will happen when I pour the other liquid into the test tube containing the yellow liquid and the blue food coloring.  Again, I asked the students to make predictions and attempt to support their predictions with logic, observations, or past experiences.   The students expectantly watched as I poured the water in to the oil and the water mixed with the food coloring to make a blue layer underneath the yellow layer.  I then had students talk with partners to explain the observation.

Of course, this is not the end of the teaching episode as I also brought out toothpicks and magnets and encouraged students to make connections between the two systems, but what I have described above is to illustrate how teachers might use the engagement of a demo to help students think deeply about how they might explain the phenomena.

Summary/Conclusion

Just because students are interested, or entertained by demos does not make them worthwhile activities.  Furthermore, simply explaining the demo to students does little to help them become critical/creative thinkers.  To avoid these kinds of pseudoteaching, try using questions to get kids generating and defending predictions and explanations.